Strip rolling



Jan. 11, 1966 Filed July 14. 1961 T. A. FOX

STRIP ROLLING 2 Sheets-Sheet l g 42 fl INVENTOR Thomas A. Fox

Jan. 11, 1966 T. A. FOX 3,228,219

STRIP ROLLING Filed July 14, 1961 2 Sheets-Sheet 2 INVENTOR Thomas A.Fox

United States Patent 3,228,219 STRIP ROLLING Thomas A. Fox, Youngstown,Ohio, assiguor to Fox Industries, Inc, a corporation of Ohio Filed July14, 1961, Ser. No. 124,092 1 Claim. (Cl. 72-16) This invention relatesto strip rolling and particularly to a means for rolling strip withcontrolled edge to edge differential. This application is acontinuation-in-part of my application Serial No. 668,989, filed July 1,1957, now US. Patent 3,024,679, issued March 13, 1962.

Strip varies sharply in its dimensions from edge to edge as well as fromend to end. These dimensional variations are undesirable but prior to myinvention disclosed in application Serial No. 668,989, no adequatesolution to any part of these difficulties had been found. The problemof controlling edge to edge contour has been particularly diflicult.

I have invented means for automatically controlling edge to centerdifferential so that strip of substantially uniform contour may berolled.

I preferably provide a housing, a pair of work rolls in the housing onopposite sides of a pass line, said work rolls being adapted to receivestrip there'between and to exert a working force transversely to thepoint thereof, journals for each end of said work rolls, backup rollsjournaled in the housing adjacent each work roll, pressure mean at theends of said work rolls acting on and moving the journals of said workrolls perpendicularly to the point of the strip to cause the ends ofsaid work rolls to move with respect to each other, so as to cause themiddle thereof to engage a strip being rolled as a fulcrum and to bendsaid work rolls about said fulcrum to provide a desired strip contour,sensing means adjacent the exit side of said work rolls at spaced pointsacross the strip width measuring the thickness of said strip, servomeans actuated by said sensing means energizing the pressure meansacting on the work roll ends whereby variations in the strip thicknessleaving the work rolls is translated into pressure changes on the workroll ends in a direction perpendicular to the pass line. Preferablymeans are provided "between the sensing means and the servo mechanismintegrating the ratings of the several sensing means so as to actuatethe servo mechanism upon a changing in differential thickness fromcenter to each edge of the strip.

In the foregoing general statement I have set out certain objects,advantages and purposes of my invention. Other objects, advantage andpurposes will be apparent from a consideration of the followingdescription and the accompanying drawings in which,

FIGURE 1 is a side elevation of a rolling mill stand according to myinvention;

FIGURE 2 is a front elevation of the mill of FIG- URE 1;

FIGURE 3 is an isometric view of the apparatus of FIGURE 1;

FIGURE 4 is an isometric view of a second embodiment of this invention;

FIGURE 5 is an isometric view of a third embodiment of this invention;and

FIGURE 6 is an isometric view of a fourth embodiment of this invention;

FIGURE 7 is a schematic view of a control circuit for controlling theflow of fluid to the pistons of the roll housing.

Referring to the drawings, I have illustrated a roll housing 10 carryingwork rolls 11 and 12 on opposite sides of a pass line 13. The upper workroll 11 is mounted in movable chocks 14 and is backed up by a back-uproll 15 mounted in chocks 15. The lower work roll 12 i mounted inmovable chocks 17 and is backed up by .back-up roll 15' mountedinback-up roll chocks 18. A hydraulic cylinder 21 is inserted betweenchocks 14 of the upper work roll and chocks 16 of the upper back-uproll. Hydraulic cylinders 21 are mounted between chocks 17 of the lowerwork roll and chocks 18 of the lower back-up roll. Hydraulic fluid isdelivered to the cylinders 20 and 21 through control valves, one foreach of the cylinders 20 and 21 of each housing from a source ofhydraulic pressure. The valves to cylinders 20 and 21 are controlled byand are a part of servo mechanisms 25 and 26 respectively. Each of theservo mechanisms is connected to a sensing means which measures thethickness of the strip. The sensing means of FIGURES 1 through 3consists of X-ray gauges 30, 31 and 32, spaced across the strip, 30 and32 at the opposite edges and 31 at the center line of the strip. Currentproduced from gauges 3t 31 and 32 is delivered to amplifiers 33, 34 and35 respectively from which it actuates the servo mechanisms 25 and 26 todeliver hydraulic fluid to the pistons to exert a force perpendiculanlyto the path of strip travel or to return hydraulic fluid from thepistons to maintain a constant gauge differential across the strip.

In FIGURE 4, I have illustrated a traversing X-ray gauge set up in whicha traversing gauge traverses the strip from the center to one edge. Thetraversing gauge 41 traverses the strip from the center to the oppositeedge. The current produced by these gauges is delivered to amplifiers 42and 43 actuating servo mechanisms 44 and 45 which control the fluidpressure in pistons 46 and 47 in one housing and 48 and 49 in theopposite housing. Preferably limit switches 58 and 51 are placed midwaybetween the center of the strip and each edge to "be contacted by thegauge halfway between the center and the edge so as to reverse thepolarity of current firom the traversing gauge. This is required becausenegative gauge at the edge requires a decrease in pressure to thecylinders acting on the work rolls.

In the embodiment illustrated in FIGURE 5, I have substituted magneticgauges 60, 61 and 62 for the X-ray gauges of FIGURES i1 through 3. Theoperation and structure of this embodiment are otherwise identical withFIGURES 1 through 3.

In the embodiment illustrated in FIGURE 6, I have substituted traversingmagnetic gauges for the traversing X-ray gauges of FIGURE 4. Thestructure is otherwise identical with FIGURE 4 and the operation islikewise identical.

In FIGURE 7 I have illustrated a form of control mechanism in which theamplified current coming from the X-ray gauges is delivered to constantspeed motors 65, 66 and 67. Motor receives current from the gauge at oneedge. Motor 67 receives current from a gauge at the opposite edge of thestrip and motor 66 receives current from the gauge at the center of thestrip. The shafts of motors 65 and 66 are connected to pinions 68 and 69on opposite sides of a differential 70, carrying planetary gears '71 and72 in planetary housing 73. Housing '73 carries a pinion 74 which drivesa control pinion 7S and thereby actuates a valve 76 in the line leadingto hydraulic cylinders 7'7 and 78 (corresponding to cylinders 46 and 47respectively of FIGURE 4) on one side of the mill. The shafts of motors66 and 67 are connected through a similar differential 81 With aplanetary housing 81 and planetary drive gear 82 which drives a controlpinion 83 operating valve 84 to control the hydraulic cylinders 85 and86 (corresponding to cylinders 48 and 49 respectively of FIGURE 4) forthe opposite end of the mill stand.

In the foregoing disclosure, I have illustrated and described certainpreferred embodiments of my invention.

However, it will be understood that this invention may be otherwiseembodied within the scope of the following claim.

' I claim: 7

A strip rolling apparatus comprising a pair of work rolls on oppositesides of a pass line, said work rolls adapted to receive striptherebetween and to exert a working force perpendicularly to the paththereof, journals for each end of said Work-rolls, back-up rollsjournaled adjacent each Work roll, pressure means at the ends of saidWork rolls acting on and moving the journals of said work rollsperpendicularly to the path of strip travel to cause the ends of saidwork rolls to move with respect to each other so as to cause themidpoint thereof to engage a strip being rolled as a fulcrum and tobendsaid work rolls about said fulcrum to provide a desired strip contour,thickness sensing means adjacent the exist side of said work rolls atspaced points across the strip width measuring the thickness of saidstrip, a constant speed servo motor actuated by said sensing means, anequation differential gear box having pinion gears driven by eachadjacent motor and a planetary housing surrounding said pair of piniongears whereby a diiference in speed of the pinion gears rotates thehousing, gear means on the housing, drive means for the pressure meansand connections between the drive means and pressure means actuated bythe gear means on the planetary housing energizing the pressure means,acting on the work roll ends whereby variations in the strip thicknessleaving the work rolls is translated into pressure changes on the Workroll ends.

References Cited by the Examiner UNITED STATES PATENTS 2,106,965 2/1938Wright et a1. 8056.1 2,792,730 5/1957 Cozzo 8038 3,006,225 10/1961 Mamas80-56 3,024,679 3/1962 Fox 8056.1

CHARLES W. LANHAM, Primary Examiner.

LEON PEAR, WILLIAM J. STEPHENSON, Examiners.

C. H. HITTSON, Assistant Examiner.

